Surveillance in ulcerative colitis: is chromoendoscopy-guided endomicroscopy always better than conventional colonoscopy? A randomized trial

Additional Yield of Random Biopsy in Patients With Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis

BACKGROUND

There are limited clinical data regarding the additional yields of random biopsies (RBs) during colorectal cancer surveillance in patients with inflammatory bowel disease. To assess the additional yield of RB, a systematic review and meta-analysis was conducted.

METHODS

PubMed, Embase, Web of Science, and the Cochrane Library were searched for studies investigating the preferred colonoscopy surveillance approach for inflammatory bowel disease patients. The additional yield, detection rate, procedure time, and withdrawal time were pooled.

RESULTS

Thirty-seven studies (48 arms) were included in the meta-analysis with 9051 patients. The additional yields of RB were 10.34% in per-patient analysis and 16.20% in per-lesion analysis. The detection rates were 1.31% and 2.82% in per-patient and per-lesion analysis, respectively. Subgroup analysis showed a decline in additional yields from 14.43% to 0.42% in the per-patient analysis and from 19.20% to 5.32% in the per-lesion analysis for studies initiated before and after 2011. In per-patient analysis, the additional yields were 4.83%, 10.29%, and 56.05% for primary sclerosing cholangitis (PSC) proportions of 0% to 10%, 10% to 30%, and 100%, respectively. The corresponding detection rates were 0.56%, 1.40%, and 19.45%. In the per-lesion analysis, additional yields were 11.23%, 21.06%, and 45.22% for PSC proportions of 0% to 10%, 10% to 30%, and 100%, respectively. The corresponding detection rates were 2.09%, 3.58%, and 16.24%.

CONCLUSIONS

The additional yields of RB were 10.34% and 16.20% for per-patient and per-lesion analyses, respectively. Considering the decreased additional yields in studies initiated after 2011, and the influence of PSC, endoscopy centers lacking full high-definition equipment should consider incorporating RB in the standard colonoscopy surveillance for inflammatory bowel disease patients, especially in those with PSC.

Clinical usefulness of image-enhanced endoscopy for the diagnosis of ulcerative colitis-associated neoplasia

Patients with a long history of ulcerative colitis (UC) are at risk of developing a significant complication known as UC-associated neoplasia (UCAN). To reduce the risk of UCAN and the associated mortality, the current guidelines recommend initiating surveillance colonoscopy 8-10 years after confirmation of UC diagnosis. In recent years, advancements in endoscopic diagnostic technologies, including magnifying and image-enhancing techniques, have allowed for the production of high-contrast images that emphasize mucosal structures, vascular patterns, and color tones. Recently, image-enhanced endoscopy technologies have become available and offer the potential to improve the qualitative endoscopic assessment of UCAN. The use of high-definition chromoendoscopy enables the evaluation of subtle mucosal patterns in the colon. Magnifying narrow-band imaging facilitates the visualization of mucosal vascular structures. Texture and color enhancement imaging processes structure, color tone, and brightness aspects more appropriately, whereas linked color imaging optimizes the emphasis on mucosal and vascular redness. Both techniques are expected to excel in the depiction of subtle color variations and mucosal changes characteristic of UCAN. This article provides an overview of the current status and future challenges regarding the use of various image-enhanced endoscopy techniques in the diagnosis of UCAN.

A Systematic Review and Meta-Analysis of Endoscopic Surveillance Studies for Detecting Dysplasia in Patients With Inflammatory Bowel Disease

Inflammatory bowel disease (IBD)is an extremely common gastrointestinal disorder that can give rise to dysplasia and colorectal cancer (CRC). There are various diagnostic methods but endoscopy has proved to be the best in the diagnosis, monitoring, and treatment of IBD. The objective of this review is to evaluate the efficacy of endoscopy in detecting patients with IBD. A structured search strategy on PubMed, Science Direct, and Google Scholar was used, as well as formal inclusion or exclusion, data extraction, validity assessment, and meta-analysis. RevMan 5.4 (Review Manager (RevMan) (Computer program). Version 5.4. The Cochrane Collaboration, 2020) was used for the meta-analysis, and forest plots were generated for each outcome separately. All of these studies are prospective cohorts and 11 of these are randomized controlled trials (RCTs). In IBD, both chromoendoscopy and white light endoscopy are useful in detecting dysplasia and neoplastic lesions. Furthermore, narrow-band imaging is a less time-consuming option for endoscopic surveillance. The meta-analysis also showed that chromoendoscopy is superior to other methods.

Role of ultra-high definition endoscopy (endomicroscopy and endocytoscopy) and real-time histologic examination in inflammatory bowel disease: Scoping review

OBJECTIVES

Confocal laser endomicroscopy (CLE) and endocytoscopy (EC) are ultra-high definition (HD) imaging modalities that enable real-time histological assessment. Although existent for nearly two decades, their role in current clinical decision making in inflammatory bowel disease management is not well defined.

METHODS

We searched PubMed using keywords ("confocal" OR "CLE" OR "endocytoscopy") AND ("IBD" OR "inflammatory bowel" OR "Crohn*" OR "Crohn's" OR "colitis ulcerosa" OR "ulcerative colitis") between 2005 and March 2023. We identified 52 studies for detailed review.

RESULTS

Confocal laser endomicroscopy was useful in real-time assessment of histologic inflammation and dysplasia characterization in both ulcerative colitis (UC) and Crohn's disease. Although CLE was associated with higher per-biopsy yield for UC-associated neoplasia (UCAN), the benefit was offset by higher procedure time, frequent equipment failure, and conflicting results on incremental yield over chromoendoscopy. Assessment of barrier dysfunction by CLE did not correlate with disease/endoscopic activity but could predict major adverse outcomes. The implications of residual CLE abnormalities in endoscopic remission remain uncertain. Ex vivo binding of labeled biologics can help in predicting biologic response in UC. EC can discriminate mucosal inflammatory cells by morphology and allows assessment of histologic activity. EC combined with pit pattern was better than pit pattern alone for UCAN. Artificial intelligence-assisted EC in UCAN needs further study.

CONCLUSION

Ultra-HD imaging in inflammatory bowel disease can be useful in assessment of UCAN, barrier dysfunction, predicting histologic remission, and biologic response. Future controlled studies are warranted to define the role of these novel technologies in clinical decision making.

High-definition chromoendoscopy results in more significant dysplasia detection than white light endoscopy with random biopsies in ulcerative colitis patients: A single-center retrospective study

The goal of this study was to determine whether high-definition white light endoscopy with random biopsies (HD-WLR) or chromoendoscopy (HDCE) yielded a higher dysplasia detection rate in ulcerative colitis patients. Ulcerative colitis (UC) patients have a 2.4-fold increased future risk of developing colorectal cancer compared to the general population and require careful dysplasia screening modalities. Both HD-WLR and HDCE are regularly used, and recent guidelines do not suggest a preference. UC patients who underwent dysplasia surveillance at our site between January 2019 and 2021 were retrospectively reviewed. We calculated the dysplasia detection rate of both techniques at the first CRC screening colonoscopy. Eighteen dysplastic lesions were detected in total, 3 by HD-WLR and fifteen by HDCE. Dysplasia was detected in 4% (3/75) and 20% (15/75) of UC patients by HD-WLR and HDCE respectively, with significantly fewer biopsies (4.44 ± 4.3 vs 29.1 ± 13.0) required using the former. HD-WLR detected 2 polypoid and one non-polypoid lesion, while HDCE detected eleven polypoid and 4 non-polypoid lesions. No invisible dysplasia or colorectal cancer was detected. Screening was performed at 10.8 ± 4.8 and 9.72 ± 3.05 years following UC diagnosis for HDCE and HD-WLR respectively. Median withdrawal time was 9.0 ± 2.7 minutes (HD-WLR) vs 9.6 + 3.9 minutes (HDCE). HDCE is associated with higher dysplasia detection rates compared to HD-WLR in a UC patient population. Given the former technique is less tedious and costly, our findings complement existing studies that suggest HDCE may be considered over HD-WLR for UC dysplasia surveillance.

Endoscopic characterization of neoplastic and non-neoplastic lesions in inflammatory bowel disease: systematic review in the era of advanced endoscopic imaging

Background

Current guidelines strongly recommend the use of validated classifications to support optical diagnosis of lesions with advanced endoscopic imaging in the lower gastrointestinal tract. However, the optimal strategy in inflammatory bowel disease (IBD) is still a matter of debate.

Objectives

To analyze the accuracy of endoscopic classifications or single predictors for in vivo lesion characterization during endoscopic surveillance of IBD with advanced endoscopic imaging.

Design

Systematic review.

Data sources and methods

Medline and PubMed were used to extract all studies which focused on lesion characterization of neoplastic and non-neoplastic lesions in IBD. The diagnostic accuracy of endoscopic classifications and single endoscopic predictors for lesion characterization were analyzed according to type of patients, lesions, and technology used. When available, the rates of true and false positives or negatives for neoplasia were pooled and the sensitivity (SE), specificity (SP), positive predictive value, and negative predictive value (NPV) were calculated.

Results

We included 35 studies (2789 patients; 5925 lesions - 1149 neoplastic). Advanced endoscopic imaging included dye-based chromoendoscopy, virtual chromoendoscopy (VCE), magnification and high-definition endoscopy, confocal laser endomicroscopy (CLE), endocytoscopy, and autofluorescence imaging. The Kudo classification of pit patterns was most frequently used, with pooled SE 83%, SP 83%, and NPV 95%. The endoscopic criteria with the highest accuracy, with minimum SE ⩾ 90%, SP ⩾ 80%, and NPV ⩾ 90% were: the Kudo-IBD classification used with VCE (Fuji Intelligent Color Enhancement and i-SCAN); combined irregular surface and vascular patterns used with narrow band imaging; the Mainz classification used with CLE. Multiple clinical and technical factors were found to influence the accuracy of optical diagnosis in IBD.

Conclusion

No single endoscopic factor has yet shown sufficient accuracy for lesion characterization in IBD surveillance. Conventional classifications developed in the non-IBD setting have lower accuracy in IBD. The use of new classifications adapted for IBD (Kudo-IBD), and new technologies based on in vivo microscopic analysis show promise.

Use of advanced endoscopic technology for optical characterization of neoplasia in patients with ulcerative colitis: Systematic review

OBJECTIVES

Advances in endoscopic technology, including magnifying and image-enhanced techniques, have been attracting increasing attention for the optical characterization of colorectal lesions. These techniques are being implemented into clinical practice as cost-effective and real-time approaches. Additionally, with the recent progress in endoscopic interventions, endoscopic resection is gaining acceptance as a treatment option in patients with ulcerative colitis (UC). Therefore, accurate preoperative characterization of lesions is now required. However, lesion characterization in patients with UC may be difficult because UC is often affected by inflammation, and it may be characterized by a distinct "bottom-up" growth pattern, and even expert endoscopists have relatively little experience with such cases. In this systematic review, we assessed the current status and limitations of the use of optical characterization of lesions in patients with UC.

METHODS

A literature search of online databases (MEDLINE via PubMed and CENTRAL via the Cochrane Library) was performed from 1 January 2000 to 30 November 2021.

RESULTS

The database search initially identified 748 unique articles. Finally, 25 studies were included in the systematic review: 23 focused on differentiation of neoplasia from non-neoplasia, one focused on differentiation of UC-associated neoplasia from sporadic neoplasia, and one focused on differentiation of low-grade dysplasia from high-grade dysplasia and cancer.

CONCLUSIONS

Optical characterization of neoplasia in patients with UC, even using advanced endoscopic technology, is still challenging and several issues remain to be addressed. We believe that the information revealed in this review will encourage researchers to commit to the improvement of optical diagnostics for UC-associated lesions.

Image-Enhanced Endoscopy in the Surveillance of Colitis-Associated Neoplasia

Advances in endoscopic technology have allowed for improved detection and management of dysplasia. These developments have also raised the question of the optimal methods for surveillance. Promising data showed that virtual chromoendoscopy (VCE) is comparable to dye-based chromoendoscopy (DCE). However, the usefulness of DCE and VCE in the surveillance of longstanding inflammatory bowel disease colitis when compared with high-definition white-light endoscopy has been recently questioned. Confocal laser endomicroscopy is a highly innovative endoscopic procedure but is still far from the routine adoption for surveillance. Thus, a personalized approach should guide the most appropriate surveillance strategy.

Innovative Diagnostic Endoscopy in Inflammatory Bowel Diseases: From High-Definition to Molecular Endoscopy

High-definition endoscopy is one essential step in the initial diagnosis of inflammatory bowel disease (IBD) characterizing the extent and severity of inflammation, as well as discriminating ulcerative colitis (UC) from Crohn's disease (CD). Following general recommendations and national guidelines, individual risk stratification should define the appropriate surveillance strategy, biopsy protocol and frequency of endoscopies. Beside high-definition videoendoscopy the application of dyes applied via a spraying catheter is of additional diagnostic value with a higher detection rate of intraepithelial neoplasia (IEN). Virtual chromoendoscopy techniques (NBI, FICE, I-scan, BLI) should not be recommended as a single surveillance strategy in IBD, although newer data suggest a higher comparability to dye-based chromoendoscopy than previously assumed. First results of oral methylene blue formulation are promising for improving the acceptance rate of classical chromoendoscopy. Confocal laser endomicroscopy (CLE) is still an experimental but highly innovative endoscopic procedure with the potential to contribute to the detection of dysplastic lesions. Molecular endoscopy in IBD has taken application of CLE to a higher level and allows topical application of labeled probes, mainly antibodies, against specific target structures expressed in the tissue to predict response or failure to biological therapies. First pre-clinical and in vivo data from label-free multiphoton microscopy (MPM) are now available to characterize mucosal and submucosal inflammation on endoscopy in more detail. These new techniques now have opened the door to individualized and highly specific molecular imaging in IBD in the future and pave the path to personalized medicine approaches. The quality of evidence was stated according to the Oxford Center of evidence-based medicine (March 2009). For this review a Medline search up to January 2021 was performed using the words “inflammatory bowel disease,” “ulcerative colitis,” “crohn's disease,” “chromoendoscopy,” “high-definition endoscopy,” “confocal laser endomicroscopy,” “confocal laser microscopy,” “molecular imaging,” “multiphoton microscopy.”

Endoscopic imaging in inflammatory bowel disease: current developments and emerging strategies

INTRODUCTION

Developments in enhanced and magnified endoscopy have signified major advances in endoscopic imaging of ileocolonic pathology in inflammatory bowel disease (IBD). Artificial intelligence is increasingly being used to augment the benefits of these advanced techniques. Nevertheless, treatment of IBD patients is frustrated by high rates of non-response to therapy, while delayed detection and failures to detect neoplastic lesions impede successful surveillance. A possible solution is offered by molecular imaging, which adds functional imaging data to mucosal morphology assessment through visualizing biological parameters. Other label-free modalities enable visualization beyond the mucosal surface without the need of tracers.

AREAS COVERED

A literature search up to May 2020 was conducted in PubMed/MEDLINE in order to find relevant articles that involve the (pre-)clinical application of high-definition white light endoscopy, chromoendoscopy, artificial intelligence, confocal laser endomicroscopy, endocytoscopy, molecular imaging, optical coherence tomography, and Raman spectroscopy in IBD.

EXPERT OPINION

Enhanced and magnified endoscopy have enabled an improved assessment of the ileocolonic mucosa. Implementing molecular imaging in endoscopy could overcome the remaining clinical challenges by giving practitioners a real-time in vivo view of targeted biomarkers. Label-free modalities could help optimize the endoscopic assessment of mucosal healing and dysplasia detection in IBD patients.

Advanced neoplasia detection using chromoendoscopy and white light colonoscopy for surveillance in patients with inflammatory bowel disease

Background/Aims

Chromoendoscopy (CE) has been shown to be superior to white light endoscopy (WLE) for neoplasia detection in inflammatory bowel disease (IBD). We aimed to compare the yield of CE and WLE for the detection of overall neoplasia and advanced neoplasia in IBD.

Methods

Patients who underwent surveillance colonoscopy from 1999 to 2017 were identified from our IBD database. CE procedures were compared with their respective WLE controls in a paired comparison, and frequency of all neoplasia, advanced neoplasia, and serrated neoplasia was assessed for both targeted and random biopsies.

Results

A total of 290 procedures performed in 98 individuals were identified with a median follow-up 4 years (median 3 colonoscopies/patient). CE and WLE were performed in 159 and 131 episodes, respectively. CE detected neoplasia in 40.9% of colonoscopies versus 23.7% with WLE (P= 0.002). In addition, CE detected more advanced neoplasia (18.2% vs. 6.1%, P= 0.002) and serrated lesions (14.5% vs. 6.1%, P= 0.022). Significantly fewer samples were obtained per procedure with CE (14.9 ± 9.7 vs. 20.9 ± 11.1, P< 0.001). Cancer was diagnosed in 2 cases.

Conclusions

CE has a higher detection rate than WLE for advanced neoplasia and serrated lesions in patients with IBD under surveillance. Further prospective studies evaluating the impact of CE on decreasing the risk of interval cancer and colectomy in IBD patients are warranted.

Meta-analysis of Virtual-based Chromoendoscopy Compared With Dye-spraying Chromoendoscopy Standard and High-definition White Light Endoscopy in Patients With Inflammatory Bowel Disease at Increased Risk of Colon Cancer

BACKGROUND

Patients with inflammatory bowel disease (IBD) have an increased risk of colorectal cancer. We sought to assess the comparative efficacy of virtual chromoendoscopy (VCE) vs high definition white light endoscopy (HDWLE) or dye-spraying chromoendoscopy (DCE) through a meta-analysis and rating the quality of evidence.

METHODS

A systematic review of the literature was performed through February 15, 2019. Primary outcomes were number of patients in whom dysplasia was identified and number of dysplastic lesions identified in these patients. We included only randomized control trials (RCTs) and performed meta-analysis using RevMan5.3.

RESULTS

Of the 3205 studies identified, 11 RCTs were included, with a total of 1328 patients. Per patient analysis, VCE was not statistically different compared with DCE (risk ratio [RR] 0.77; 95% CI, 0.55-1.08) or HDWLE (RR 0.72; 95% CI, 0.45-1.15). However, per dysplasia analysis, VCE was not statistically different compared with DCE (RR 0.72; 95% CI, 0.47-1.11) and inferior compared with HDWLE (RR 0.62; 95% CI, 0.44-0.88). The quality of evidence was moderate in the HDWLE and low to moderate in the DCE studies.

CONCLUSION

Based on this meta-analysis, VCE was as good as HDWLE and DCE in identifying dysplasia per patient analysis. However, per dysplasia analysis, VCE was inferior compared with HDWLE and no different from DCE. Further studies need to examine the efficacy of each individual VCE technique.

Surveillance in inflammatory bowel disease: is chromoendoscopy the only way to go? A systematic review and meta-analysis of randomized clinical trials

Background and study aims  Ulcerative colitis (UC) and Crohn's disease (CD) have higher risk of colorectal cancer (CRC). Guidelines recommend dysplasia surveillance with dye-spraying chromoendoscopy (DCE). The aim of this systematic review and meta-analysis was to review all randomized clinical trials (RCTs) available and compare the efficacy of different endoscopic methods of surveillance for dysplasia in patients with UC and CD. Methods  Databases searched were Medline, EMBASE, Cochrane and SCIELO/LILACS. It was estimated the risk difference (RD) for dichotomous outcomes (number of patients diagnosed with one or more dysplastic lesions, total number of dysplastic lesions diagnosed and number of dysplastic lesions detected by targeted biopsies) and mean difference for continuous outcomes (procedure time). Results  This study included 17 RCTs totaling 2,457 patients. There was superiority of DCE when compared to standard-definiton white light endoscopy (SD-WLE). When compared with high-definition (HD) WLE, no difference was observed in all outcomes (number of patients with dysplasia (RD 0.06; 95 % CI [-0.01, 0.13])). Comparing other techniques, no difference was observed between DCE and virtual chromoendoscopy (VCE - including narrow-band imaging [NBI], i-SCAN and flexible spectral imaging color enhancement), in all outcomes except procedure time (mean difference, 6.33 min; 95 % CI, 1.29, 11.33). DCE required a significantly longer procedure time compared with WLE (mean difference, 7.81 min; 95 % CI, 2.76, 12.86). Conclusions  We found that dye-spraying chromoendoscopy detected more patients and dysplastic lesions than SD-WLE. Although no difference was observed between DCE and HD-WLE or narrow-band imaging, the main outcomes favored numerically dye-spraying chromoendoscopy, except procedure time. Regarding i-SCAN, FICE and auto-fluorescence imaging, there is still not enough evidence to support or not their recommendation.

Surgical Management of Dysplasia and Cancer in Inflammatory Bowel Disease

Patients with inflammatory bowel disease are at an increased risk of cancer secondary to long-standing intestinal inflammation. Surgical options must take into account the significant risk of synchronous disease at other colonic sites. Ileal pouch anal anastomosis is a viable option for patients with ulcerative colitis, but this should be restricted to early cancers that are unlikely to require preoperative or postoperative radiation treatment.

Systematic review with network meta-analysis: endoscopic techniques for dysplasia surveillance in inflammatory bowel disease

BACKGROUND

International guidelines recommend dysplasia surveillance in IBD.

AIM

To compare endoscopic techniques for dysplasia surveillance METHODS: We searched MEDLINE, Embase, CENTRAL for randomised trials through May 2019. We estimated odds ratios (ORs) for binary and mean differences (MDs) for continuous outcomes, using frequentist random-effects network meta-analysis. We assessed study risk of bias and appraised evidence certainty using GRADE.

RESULTS

Eighteen trials (2638 participants) were included. Standard definition white-light endoscopy (OR 0.44, 95% CI 0.26-0.73; high certainty) and i-SCAN (OR 0.47, 95% CI 0.25-0.90; moderate certainty) had lower odds of detecting neoplasia than chromoendoscopy. Fujinon intelligent colour enhancement (FICE), standard definition white-light endoscopy and i-SCAN had lower odds for this outcome than full spectrum high definition white-light endoscopy (ORs 0.02 to 0.15; low certainty). Standard definition white-light endoscopy had lower odds of detecting nonpolypoid neoplasia than full spectrum high definition white-light endoscopy, narrow band imaging, chromoendoscopy and high definition white-light endoscopy (ORs 0.01-0.14; moderate certainty). Full spectrum high definition white-light endoscopy ranked as the best technique for both outcomes (moderate certainty). Standard definition white-light endoscopy had lower odds of detecting neoplasia by target biopsy (OR 0.27, 95% CI 0.08-0.91) and had shorter procedure time (MD -14.81 minutes, 95% CI -25.03, -4.06) than chromoendoscopy (moderate certainty).

CONCLUSIONS

Chromoendoscopy, high definition white-light endoscopy, narrow band imaging, autofluorescence, FICE and full spectrum high definition white-light endoscopy may be comparable for dysplasia surveillance. Standard definition white-light endoscopy and i-SCAN probably provide lower yields for neoplasia identification. Full spectrum high definition white-light endoscopy may represent the first-line approach.

Meta-analysis of dye-based chromoendoscopy compared with standard- and high-definition white-light endoscopy in patients with inflammatory bowel disease at increased risk of colon cancer

BACKGROUND

Patients with ulcerative colitis have an increased risk of colorectal cancer. We sought to assess the comparative efficacy of standard white-light endoscopy (SDWLE) or high-definition white-light endoscopy (HDWLE) versus dye-based chromoendoscopy through a meta-analysis and rate the quality of evidence using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) system.

METHODS

A systematic review of the literature in PubMed, EMBASE, and Web of Science was performed in April 2018. The primary outcome was the number of patients in whom dysplasia was identified using a per patient analysis in randomized controlled trials (RCT) and analyzed separately for non-RCTs. Analysis was performed using RevMan 5.3 reporting random-effects risk ratios.

RESULTS

Of the 27,904 studies identified, 10 studies were included 6 of which were RCTs (3 SDWLE and 3 HDWLE). Seventeen percent (84/494) of patients were noted to have dysplasia using chromoendoscopy compared with 11% (55/496) with white-light endoscopy (relative risk [RR] 1.50; 95% confidence interval [CI], 1.08-2.10). When analyzed separately, chromoendoscopy (n = 249) was more effective at identifying dysplasia than SDWLE (n = 248) (RR, 2.12; 95% CI, 1.15-3.91), but chromoendoscopy (n = 245) was not more effective compared with HDWLE (n = 248) (RR, 1.36; 95% CI, 0.84-2.18). The quality of evidence was moderate. In non-RCTs, dysplasia was identified in 16% (114/698) of patients with chromoendoscopy compared with 6% (62/1069) with white-light endoscopy (RR, 3.41; 95% CI, 2.13-5.47). Chromoendoscopy (n = 58) was more effective than SDWLE (n = 141) for identification of dysplasia (RR, 3.52; 95% CI, 1.38-8.99), and chromoendoscopy (n = 113) was also more effective than HDWLE (n = 257) (RR, 3.15; 95% CI, 1.62-6.13). The quality of the evidence was very low.

CONCLUSION

Based on this meta-analysis, non-RCTs demonstrate a benefit of chromoendoscopy over SDWLE and HDWLE, whereas RCTs only show a small benefit of chromoendoscopy over SDWLE, but not over HDWLE.

Augmented Endoscopy for Surveillance of Colonic Inflammatory Bowel Disease: Systematic Review With Network Meta-analysis

INTRODUCTION

Considering the high risk of dysplasia and cancer in inflammatory bowel disease [IBD], surveillance is advocated. However, international guidelines do not reach a uniform recommendation on the way to perform surveillance. We performed a systematic review with a meta-analysis to assess the best endoscopic surveillance strategy in colonic IBD.

METHODS

The systematic review was performed in PubMed/MEDLINE, EMBASE, SCOPUS, and Cochrane databases to identify studies comparing white light endoscopy [WLE] and augmented endoscopy [AE] in the detection of dysplasia/neoplasia in colonic IBD. A sub-analysis between dye-spray chromoendoscopy [DCE], narrow-band imaging [NBI], I-SCAN, full-spectrum endoscopy [FUSE], and auto-fluorescence imaging [AFI] was also performed. Furthermore, a meta-regression and a network meta-analysis were also performed.

RESULTS

A total of 27 studies [6167 IBD patients with 2024 dysplastic lesions] met the inclusion criteria. There was no publication bias. AE showed a higher likelihood of detecting dysplasia than WLE (19.3% vs 8.5%, odds ratio [OR] = 2.036), with an incremental yield [IY] of 10.8%. DCE [OR = 2.605] and AFI [OR = 3.055] had higher likelihood of detecting dysplasia than WLE; otherwise, I-SCAN [OR = 1.096], NBI [OR = 0.650], and FUSE [OR = 1.118] were not superior to WLE. Dysplasia was found in 1256/7267 targeted biopsies [17.3%] and in 363/110 040 random biopsies [0.33%] [OR = 66.559, IY = 16.9%]. Meta-regression found no variable impacting on the efficacy of AE techniques. Network meta-analysis identified a significant superiority of DCE to WLE in detecting dysplasia [OR 2.12], but no other single technique was found to be superior to all others in dysplasia detection.

CONCLUSIONS

DCE was associated with higher likelihood of discovering dysplastic lesions than WLE. Chromoendoscopy is the best supported endoscopic technique for IBD surveillance.

Endoscopic surveillance strategies for dysplasia in ulcerative colitis

Ulcerative colitis (UC) is a chronic inflammatory bowel disorder with an increased risk of colorectal cancer (CRC). This has led to the implementation of surveillance programmes to minimise this risk. Overall, these proactive programmes in association with better medical therapies have reduced the incidence of CRC in this population. Specific populations remain at increased risk, such as younger age at diagnosis, primary sclerosing cholangitis, colonic strictures and pseudopolyps. The majority of gastrointestinal international societies favour chromoendoscopy with targeted biopsies or random biopsies. The aim of this review is to present the current literature on dysplasia surveillance, the methodology and endoscopic technology available to assess dysplasia in UC.

Systematic review with meta-analysis: Chromoendoscopy versus white light endoscopy in detection of dysplasia in patients with inflammatory bowel disease

OBJECTIVE

To compare chromoendoscopy (CE) and white light endoscopy (WLE) for dysplasia surveillance in patients with inflammatory bowel disease (IBD).

METHODS

We conducted a meta-analysis of 6 randomized controlled trials (RCTs) and 5 prospective studies and compared the CE and WLE groups. A fixed-effect model was used unless the heterogeneity was high.

RESULTS

CE detected more patients with dysplasia (relative risk [RR] 2.05, 95% confidence interval [CI]: 1.62-2.61) and more dysplastic lesions (RR 2.04, 95% CI: 1.40-2.98) than WLE. When magnification was added to CE, the detection rate of patients with dysplasia and dysplastic lesions improved. CE also detected more patients with dysplasia than high-definition WLE (RR 1.60, 95% CI: 1.11-2.29). Compared with WLE, the incremental yield of CE for detecting patients with dysplasia was 9%. CE was superior to WLE in detecting non-polypoid dysplastic lesions (RR 1.38, 95% CI:1.02-1.88). CE had no advantage for detecting polypoid dysplastic lesions compared with WLE.

CONCLUSIONS

CE is superior to WLE in the surveillance of dysplasia in IBD patients. It is thus necessary to use CE in the surveillance of dysplasia in patients with IBD in clinical practice. Adding magnification improves the detection rate.

Modern Endoscopic Imaging in Diagnosis and Surveillance of Inflammatory Bowel Disease Patients

Endoscopy remains the most important diagnostic and monitoring modality in the management of inflammatory bowel disease. Advances in imaging have progressively added new tools into the armamentarium of endoscopists with the goal of more accurate, sensitive, and accessible visual diagnoses for the benefit of patients with gastrointestinal diseases. Here, we review the relevant literature regarding commonly used endoscopic techniques (dye-based and digital chromoendoscopy, high-definition endoscopy, capsule endoscopy, and endosonography), as well as advanced and experimental technologies (full-spectrum endoscopy, endocytoscopy, autofluorescence, laser endoscopy, and endomicroscopy, including molecular imaging), applicable to inflammatory bowel diseases and emerging for implementation into everyday practice. Additionally, we discuss future directions and techniques as candidates for a superior inflammation imaging in the diagnosis and prediction of therapeutic response.

Colonic lesion characterization in inflammatory bowel disease: A systematic review and meta-analysis

AIM

To perform a systematic review and meta-analysis for the diagnostic accuracy of in vivo lesion characterization in colonic inflammatory bowel disease (IBD), using optical imaging techniques, including virtual chromoendoscopy (VCE), dye-based chromoendoscopy (DBC), magnification endoscopy and confocal laser endomicroscopy (CLE).

METHODS

We searched Medline, Embase and the Cochrane library. We performed a bivariate meta-analysis to calculate the pooled estimate sensitivities, specificities, positive and negative likelihood ratios (+LHR, -LHR), diagnostic odds ratios (DOR), and area under the SROC curve (AUSROC) for each technology group. A subgroup analysis was performed to investigate differences in real-time non-magnified Kudo pit patterns (with VCE and DBC) and real-time CLE.

RESULTS

We included 22 studies [1491 patients; 4674 polyps, of which 539 (11.5%) were neoplastic]. Real-time CLE had a pooled sensitivity of 91% (95%CI: 66%-98%), specificity of 97% (95%CI: 94%-98%), and an AUSROC of 0.98 (95%CI: 0.97-0.99). Magnification endoscopy had a pooled sensitivity of 90% (95%CI: 77%-96%) and specificity of 87% (95%CI: 81%-91%). VCE had a pooled sensitivity of 86% (95%CI: 62%-95%) and specificity of 87% (95%CI: 72%-95%). DBC had a pooled sensitivity of 67% (95%CI: 44%-84%) and specificity of 86% (95%CI: 72%-94%).

CONCLUSION

Real-time CLE is a highly accurate technology for differentiating neoplastic from non-neoplastic lesions in patients with colonic IBD. However, most CLE studies were performed by single expert users within tertiary centres, potentially confounding these results.

Chromoendoscopy for Surveillance in Ulcerative Colitis and Crohn's Disease: A Systematic Review of Randomized Trials

BACKGROUND & AIMS

Key international guideline agencies recommend dysplasia surveillance in inflammatory bowel diseases with chromoendoscopy. We performed a systematic review of randomized trials comparing chromoendoscopy vs other endoscopic techniques for dysplasia surveillance in inflammatory bowel diseases.

METHODS

We searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials for relevant studies published through September 2016. We estimated risk ratios (RRs) for dichotomous outcomes (all-cause/colorectal cancer-related mortality, time to interval cancer, patients with dysplasia, total/subtypes of dysplastic lesions, dysplasia detected by targeted biopsies, adverse events), mean differences for continuous outcomes (procedural time, costs, total/targeted biopsies), and their 95% confidence intervals (CIs) using a random-effects model. Subgroup analyses included technique compared with chromoendoscopy, type of disease, and type of dye. We estimated sensitivity and specificity of the techniques with reference to histology.

RESULTS

We identified 10 randomized trials (n = 1500 participants). There was a higher likelihood of detecting patients with dysplasia with chromoendoscopy compared with other techniques (RR, 1.37; 95% CI, 1.04-1.79). Subgroup analyses confirmed this effect only if chromoendoscopy was compared with standard-definition white-light endoscopy (RR, 2.12; 95% CI, 1.15-3.91). Chromoendoscopy required a significantly longer procedural time compared with other techniques (mean difference, 8.91 min; 95% CI, 1.37-16.45). There was no difference in the likelihood of detecting dysplastic subtypes and dysplasia by targeted biopsies between groups. Test sensitivity and specificity were similar between groups.

CONCLUSIONS

In surveillance of inflammatory bowel diseases, chromoendoscopy identifies more patients with dysplasia only when compared with standard-definition white-light endoscopy. It is associated with longer procedural time with no direct evidence of effect on preventing all-cause/cancer-specific mortality or time to interval cancer.

Role of Advanced Endoscopic Imaging Techniques in the Management of Inflammatory Bowel Disease

Endoscopy plays a crucial role in the management of inflammatory bowel disease (IBD) in terms of diagnosis, monitoring of mucosal status, and surveillance of colitis-associated neoplasia. Mucosal healing evaluated by endoscopy has been recognized as the target of treatment in the era of powerful biologics therapy. The optimal modality for identifying dysplasia in IBD has yet to be well defined. Increasing progress has recently been made in endoscopic technologies to more accurately assess mucosal inflammation and more effectively detect dysplasia. Here we review the data of advanced endoscopic imaging techniques such as chromoendoscopy, virtual chromoendoscopy, endocytoscopy, and confocal laser endomicroscopy in the management of IBD.

Dysplasia and colorectal cancer surveillance in inflammatory bowel disease

Inflammatory bowel disease (IBD) patients are at an increased risk of developing colorectal cancer (CRC), a devastating complication of which intestinal dysplasia is the precursor. Considerable progress has been made to determine CRC risk in IBD, identification & management of dysplasia and preventative methods. Traditionally, surveillance colonoscopies with random colonic biopsies was used. However recent data suggests that chromoendoscopy is a better method of surveillance. Using 5-aminosalicylic acid agents primarily for chemoprevention is an ongoing debate however, when prescribed along with other strategies to control inflammation, their use is considered of benefit. This review presents current understanding of risk factors of neoplasia focusing on dysplasia and preventive strategies. Areas covered: PubMed search was done using key words to assess current evidence. Along with genetics, risk factors, strategies that modify the risk of dysplasia, and CRC in IBD are discussed in detail. Expert commentary: The role of our strategies in modifying CRC risk needs further assessment. Future research should aim to fill knowledge gaps such as high quality evidence for Chromoendoscopy and development of molecular markers for dysplasia detection. Our ultimate goal would be to eliminate CRC and is possible by better understanding of key pathogenic mechanisms in IBD.

Advanced endoscopy imaging in inflammatory bowel diseases

BACKGROUND AND AIMS

Rapid assessment of mucosal inflammation is of crucial importance for the initial diagnosis and the assessment of mucosal healing in inflammatory bowel disease (IBD). Moreover, the identification of intraepithelial neoplasias in IBD is of key relevance for clinical management. Here, we systematically analyzed the utility of advanced endoscopic imaging techniques for optimized diagnosis in IBD.

METHODS

PubMed/Medline, Web of Knowledge, and Cochrane library were searched twice for diagnostic studies on advanced endoscopic imaging in IBD. Clinical and technical information was retrieved and subsequently analyzed. Main outcome parameters consisted of the quality of the results, adverse events, and diagnostic yield.

RESULTS

Fifty-six clinical studies with a total of 3296 patients were selected for final analysis. Filter technologies permitted a more detailed analysis of mucosal inflammation in IBD. In spite of substantial heterogeneity across studies, dye-based chromoendoscopy with targeted biopsy sampling yielded higher detection rates of intraepithelial neoplasias in ulcerative colitis as compared with white-light endoscopy with random biopsy sampling. Moreover, endocytoscopy and endomicroscopy allowed subsurface imaging of inflamed or neoplastic mucosa in IBD at subcellular resolution. Finally, endomicroscopy-aided molecular imaging enabled the identification of membrane-bound tumor necrosis factor on mucosal cells as a potential driver of disease activity in Crohn's disease. No relevant adverse events were reported.

CONCLUSIONS

Advanced endoscopic imaging technologies are feasible, safe, and partially effective tools for detailed diagnosis of mucosal inflammation and detection of neoplasias in IBD. Results obtained from these advanced techniques may provide a rational basis for individualized, optimized therapy for IBD patients.

Advances in endoscopic imaging in ulcerative colitis

Modern strategies for the treatment of ulcerative colitis require more accurate tools for gastrointestinal imaging to better assess mucosal disease activity and long-term prognostic clinical outcomes. Recent advances in gastrointestinal luminal endoscopy are radically changing the role of endoscopy in every-day clinical practice and research trials. Advanced endoscopic imaging techniques including high-definition endoscopes, optical magnification endoscopy, and various chromoendoscopy techniques have remarkably improved endoscopic assessment of ulcerative colitis. More recently, optical biopsy techniques with either endocytoscopy or confocal laser endomicroscopy have shown great potential in predicting several histological changes in real time during ongoing endoscopy. Here, we review current applications of advanced endoscopic imaging techniques in ulcerative colitis and present the most promising upcoming headways in this field.

Surveillance of long-standing colitis: the role of image-enhanced endoscopy

Patients with long-standing inflammatory bowel disease of the colon are at an increased risk of developing colorectal carcinoma. Surveillance programs have been implemented with the aim of detecting neoplastic lesions in an early stage. Due to limitations of conventional white light endoscopy, several new techniques to enhance the detection of dysplastic lesions in this setting have been explored. These advanced endoscopic techniques use a variety of methods to improve visualization, such as pancolonic dye-spraying (chromoendoscopy), optical filters (narrow-band imaging) and autofluorescence of mucosal tissue (autofluorescence imaging). At present, most guidelines have adopted chromoendoscopy as the preferred method for surveillance, based on several controlled studies. It is currently unknown if widespread implementation of chromoendoscopy will lead to an improved clinical outcome. This review explores the current evidence on image-enhanced endoscopic techniques used in the detection of neoplastic lesions in patients with long standing colitis.